1. Field of the Invention
This invention relates to tape sticking and more particularly relates to dynamically detecting tape sticking and tape breakage.
2. Description of the Related Art
Data storage systems frequently use magnetic tape as a cost effective storage media. Magnetic tape is hereafter referred to as tape. The tape is typically stored on a first reel within a cartridge. The cartridge may be inserted into a tape drive so that data may be read from the tape or the data may be written to the tape.
An end of the tape is spooled around a second reel within the tape drive. Servos motivate the first and second reels to move the tape over a head. The head includes read elements that read data from the tape and write elements that write data to the tape. The data is encoded as magnetically polarized areas on the tape.
The tape is typically written with very high data densities. As a result, the tape must be positioned very near the head in order for the read elements to read the data and the write elements to write the data. However, the tape drive frequently stops and/or reverses the movement of the tape. When the tape is stopped, the tape may stick to the head.
A stuck tape is a serious problem. The pulling servo may continue to exert a force on the tape. If the tape becomes unstuck, the pulling servo may accelerate and damage the tape. Alternatively, the feeding servo may continue to feed tape in the tape path, damaging the tape.